At present, handheld electronic products, such as tablets, mobile phones, etc., have been widely used in people's daily lives. The handheld electronic products need to be thin and easy to manufacture to meet market demand. An accessory of the handheld electronic product usually sets a dock to expand its additional functions (such as high-power speakers, charging, etc.) to increase the value of the handheld electronic product.
When the appearance of the handheld electronic product changes, the connecting structure connecting the handheld electronic product to the accessories, such as a tablet and a dock, will be changed too. It is necessary to add a suitable limit structure and a suitable guide structure on the tablet computer or the dock to prevent the dock from crashing at the moment the tablet is inserted into the dock. The service life of the tablet and the dock can be reduced because of the crash. If the dock has a speaker, the dock can generate a transient noise at the moment the tablet is inserted into the dock, and the transient noise makes the user feel uncomfortable.